POS1285 PERIPHERAL MICROVASCULAR FUNCTION IS LINKED TO CARDIAC INVOLVEMENT ON CMR IN SYSTEMIC SCLEROSIS-RELATED PULMONARY ARTERIAL HYPERTENSION PATIENTS
Authors: J. Vos, J. Lemmers, S. Elmessaoudi, M. Snoeren, A. Van Dijk, T. Duijnhouwer, L. Rodwell, S. Van Leuven, M. Post, M. Vonk, R. Nijveldt
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Systemic sclerosis (SSc) is characterized by vasculopathy, inflammation and fibrosis, and carries one of the worst prognoses if patients also develop pulmonary arterial hypertension (PAH). Although PAH is a known prognostic factor, SSc-PAH patients demonstrate disproportionately high mortality, presumably due to cardiac involvement [1]. <h3>Objectives</h3> To investigate the relation between cardiac involvement as revealed by Cardiovascular Magnetic Resonance (CMR) and systemic microvascular disease severity as measured with nailfold capillaromicroscopy (NCM) in SSc-PAH patients, compared to idiopathic PAH (IPAH) patients. <h3>Methods</h3> SSc-PAH and IPAH patients underwent CMR, transthoracic echocardiography (TTE), and NCM with post-occlusive reactivity hyperemia (PORH) testing on the same day [2-4]. CMR imaging included T2 mapping, native and postcontrast T1 mapping, to assess edema and fibrosis, and adenosine-stress perfusion imaging to measure the relative myocardial upslope (to determine microvascular coronary perfusion). Measures of peripheral microvascular function were related to CMR indices of edema, fibrosis and myocardial perfusion. <h3>Results</h3> SSc-PAH patients (n=20) had higher extracellular volume fraction (ECV) and T2 values than IPAH patients (n=5), and lower nailfold capillary density (NCD) and reduced capillary recruitment after PORH. NCD correlated with native T1, ECV, and T2 values (r=-0.431, -0.443, and -0.464, respectively, p&lt;0.05 for all), and with markers of diastolic dysfunction on echocardiography. Furthermore, PORH-testing, but not NCD, correlated with the relative myocardial upslope by stress CMR (r=0.421, p&lt;0.05) (Table 1). <h3>Conclusion</h3> SSc-PAH patients showed higher markers of cardiac fibrosis and inflammation, compared to IPAH patients. These markers correlated well with peripheral microvascular dysfunction, suggesting that SSc-driven inflammation and vasculopathy concurrently affect peripheral microcirculation and the heart. This may contribute to the disproportionately high mortality in SSc-PAH patients. <h3>References</h3> [1]Chung L, Domsic RT, Lingala B, Alkassab F, Bolster M, Csuka ME, et al. Survival and predictors of mortality in systemic sclerosis-associated pulmonary arterial hypertension: outcomes from the pulmonary hypertension assessment and recognition of outcomes in scleroderma registry. Arthritis Care Res (Hoboken). 2014;66(3):489-95. [2]Smith V, Herrick AL, Ingegnoli F, Damjanov N, Angelis, Denton CP, et al. Standardisation of nailfold capillaroscopy for the assessment of patients with Raynaud's phenomenon and systemic sclerosis. Autoimmun Rev. 2020:102458. [3]Liu A, Wijesurendra RS, Liu JM, Greiser A, Jerosch-Herold M, Forfar JC, et al. Gadolinium-Free Cardiac MR Stress T1-Mapping to Distinguish Epicardial From Microvascular Coronary Disease. J Am Coll Cardiol. 2018;71(9):957-68. [4]Serne EH, Gans RO, ter Maaten JC, Tangelder GJ, Donker AJ, Stehouwer CD. Impaired skin capillary recruitment in essential hypertension is caused by both functional and structural capillary rarefaction. Hypertension. 2001;38(2):238-42. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Jaqueline Vos: None declared, Jacqueline Lemmers: None declared, Saloua ElMessaoudi: None declared, Miranda Snoeren: None declared, Arie van Dijk: None declared, Toon Duijnhouwer: None declared, Laura Rodwell: None declared, Sander van Leuven: None declared, Marco Post Speakers bureau: Janssen, Consultant of: Janssen, MSD, Grant/research support from: Janssen, St. Antonius Research fund, ZonMw, Madelon Vonk Speakers bureau: Boehringer Ingelheim, Bristol-Myers Squibb, GSK, Janssen, MSD, Novartis and Roche, Consultant of: Boehringer Ingelheim and Janssen, Grant/research support from: Boehringer Ingelheim, Janssen, Ferrer and Galapagos, Robin Nijveldt Speakers bureau: Sanofi, BMS, Bayer, Boerhinger Ingelheim, Consultant of: Sanofi, BMS, Grant/research support from: Philips Volcano, Biotronik.